Question

C7.1

Consider a single-loop RL circuit just like the one in activity 1. When the applied voltage is equal to 4.5V, the current also has a nonzero value. When the applied voltage drops to zero, the current in the circuit does not go to zero instantaneoulsy. Explain why the current does not go to zero instantaneously.

Please let me have reason, theroy and answer.

Answer 1

:  As I like to think of it, the L-component in the circuit, which is called an inductor, is the electrical analogy of inertia. The inductor is what causes the current to keep flowing if it is already flowing, and to be hard to start flowing if there is no current. Essentially, it resists changes in the current.

The inductor's self-EMF will keep pushing the current forward through the circuit, to get dissipated in the resistor. If there is current, the inductor will try to keep that current, exhibiting a voltage drop against any rate of change in current. For the resistor, if there is current, the resistor will try to make that current decrease, exhibiting a voltage drop against its flow.